1. Field
Exemplary embodiments of the inventive concept relate to a method for measuring a reaction rate of a reactive mesogen. More particularly, exemplary embodiments of the inventive concept relate to a method for measuring a reaction rate of a reactive mesogen according to an ultraviolet process or a thermal process, by including a marking compound capable detectable by spectroscopy.
2. Discussion of the Background
A liquid crystal display apparatus is one of the most widely used types of flat panel display FPD. Examples of a flat panel display include, but are not limited to, a liquid crystal display (“LCD”), a plasma display panel (“PDP”) and an organic light emitting display (“OLED”).
The liquid crystal display apparatus applies voltages to liquid crystal molecules to control the orientation thereof. As a result, optical characteristics of the liquid crystal cell, such as birefringence, optical activity, dichroism, and light scattering, may be controlled to display an image.
A liquid crystal display apparatus includes a liquid crystal display panel and a backlight assembly. Liquid crystal molecules of the liquid crystal display panel may be aligned in a specific direction to obtain a uniform brightness and a high contrast ratio.
Generally, a liquid crystal display apparatus includes a reactive mesogen in the liquid crystal to align the liquid crystal molecules. The reactive mesogen may be reacted via an ultraviolet process to pre-tilt of the liquid crystal.
Recently, an alignment layer including a reactive mesogen has been developed, to improve transmissivity and response time. The alignment layer may be formed from an alignment liquid that includes a compound including a polyimide molecule as a backbone and a reactive mesogen as a side chain.
Physical or chemical properties of the reactive mesogen and the backbone are similar with each other, so that it is difficult to measure a reaction rate of the reactive mesogen during the ultraviolet process. Thus, a smear on the liquid crystal display apparatus may be generated by a remaining reactive mesogen.